Analysis of supramolecular self-assembly of two chromene derivatives: Synthesis, crystal structure, Hirshfeld surface, quantum computational and molecular docking studies

Structure-property relationship in thioxotriaza-spiro derivative: Crystal structure and molecular docking analysis against SARS-CoV-2 main protease

Detailed structural and non-covalent interactions in thioxotriaza-spiroderivative (DZ2) are investigated by single crystal structure anslysis and computational approaches. Its results were compared with the previously reported spiroderivative (DZ1). The crystal structure analysis revealed various C–H…O, N–H…O, C–H…N and N–H…S hydrogen bonds involved in constructing several dimeric motifs to stabilize the crystal packing. The differences and similarities in the relative contribution of non-covalent interactions in DZ1 and DZ2 compounds are compared using the Hirshfeld surface analysis and 2D fingerprint plots. The binding energies of specific molecular pairs and homodimers have been obtained using molecule–molecule interaction energy calculation. The hierarchy and topology of pair-wise intermolecular interactions are visualized through energy frameworks. The nature and strength of intra and intermolecular interactions were characterized using non-covalent interaction index analysis and the quantum theory of atoms in molecule approach. Further, molecular docking of compounds (DZ1 and DZ2) with SARS-CoV-2 main protease for COVID-19 is performed. And the superposition of these ligands and inhibitor N3, which is docked into the binding pocket of 7BQY, is presented. The binding affinity of −6.7 kcal/mol is observed, attributed to hydrogen bonding and hydrophobic interactions between the ligand and the amino acid residues of the receptor.

Water Mediated One-Pot, Stepwise Green Synthesis, Anti-Inflammatory and Analgesic Activities of (3-Amino-1-Phenyl-1H-Benzo[f]Chromen-2-yl) (1H-Indol-3-yl) Methanone Catalysed by L-Proline

AIM

The reactions were carried out by one pot three-component synthesis, 3-cyanoacetylindole (1) on reaction with aromatic aldehydes (2) and β-naphthol (3) in an aqueous medium in presence of L-proline as a catalyst under reflux for 30 min, resulted (3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl)methanone (4). The method has many advantages like short reaction times, good yields and simple workup procedure besides being green in nature. Pharmacological evaluation of title compounds was done for anti-inflammatory and analgesic activities. Anti-inflammatory activity was carried carrageenan-induced paw edema model in which indomethacin was used as standard and analgesic activity was evaluated by eddy's hot plate method using diclofenac as standard drug.

BACKGROUND

Benzopyrans or chromenes are an important class of heterocyclic compounds due to their broad spectrum of biological activity and a wide range of applications in medicinal chemistry. The chromene moiety is found in various natural products with interesting biological properties. Chromenes constitute the basic backbone of various types of polyphenols and are widely found in alkaloids, tocopherols, flavonoids and anthocyanins. Indoles are omnipresent in various bioactive compounds like alkaloids, agrochemicals and pharmaceuticals.

OBJECTIVE

To synthesize one-pot stepwise Green synthesis, anti-inflammatory and analgesic activities of 3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl)methanones Methods: The acute anti-inflammatory effect was evaluated by carrageenan-induced mice paw edema (Ma Rachchh et al., 2011). Edema was induced by injecting carrageenan (1% w/v, 0.1 ml) in the right hind paw of mice. The test compounds 1-12, indomethacin (10 mg/kg) and the vehicle were administered orally one hour before injection of carrageenan. Paw volume was measured with digital plethysmometer at 0, 30, 60, 90, 120 min after injection. Percentage increase =A-B/ A *100 Results: Carrageenan Induced paw edema model was used for Anti-inflammatory activity in which animals treated with standard (indomethacin) and test compounds showed a significant decrease in the paw edema. Analgesic activity was estimated by using Eddy's hot plate method; animals were treated with standard (diclofenac) and test compounds showed a significant increase in the reaction time.

CONCLUSION

A green, One-pot, step-wise and three-component synthesis of 3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl) methanone was achieved by using water as a solvent, L-proline as catalyst under reflux conditions. The reactions were carried out in eco-friendly conditions with shorter reaction times, easier workup and high yields. Anti-inflammatory activity was evaluated by carrageenan-induced paw edema model where significant anti-inflammatory activity is shown by all the test compounds (4a-l) when compared to standard drug. Analgesic activity was studied by Eddy's Hot plate method and Test compounds 4e, 4f, 4h, 4i, 4j, 4k, 4l showed significant activities when compared to the reference drug.